Document Storage System

ABSTRACT

A document storage device for storing sheet documents is disclosed. The device comprises a band ( 3 ), which can be wound onto a document storage roller ( 2 ) such that sheet documents can be stored between adjacent windings of the band on the document storage roller and which can be unwound from the document storage roller thereby dispensing the stored documents, and a scraper assembly rotatable about a pivot ( 21 ) and comprising a scraper ( 19 ) and an end stop ( 20 ), each for contacting the band on the document storage roller. The scraper assembly is urged by a first biassing element ( 22 ) such that the end stop maintains contact with the band on the document storage roller at a point distal from the pivot relative to the point of contact of the scraper with the band on the document storage roller.

This invention relates to a document storage system that stores sheet documents between adjacent windings of a band wound onto a storage roller.

Such types of document storage systems are well known, particularly for storage of documents of value such as banknotes. They typically comprise a band roller and a document storage roller, to each of which are attached the opposite ends of a band. The band roller stores the band that is not currently in use, and the band is transferred, by rotating the two rollers, from the band roller onto the document storage roller when it is desired to store a banknote. The banknote to be stored is supplied to the band near to where it is wound onto the document storage roller such that the banknote is entrapped between adjacent windings of the band on the document storage roller.

By rotating the two rollers in the opposite direction, the band is transferred from the document storage roller to the band roller. Documents stored between the windings on the document storage roller are thus released.

It has been found necessary to provide a scraper to assist with releasing documents from the document storage roller. The scraper is a blade-like element that is urged into contact with the band on the document storage roller and engages the leading edge of documents as they are released to ensure that they peel off the band and into a document transport system for onward conveyance.

However, existing scraper systems suffer from poor reliability due to local variations in the diameter of the document storage roller. These variations are caused by the thickness of documents stored on the document storage roller between the windings of the band. The variations are transmitted into the scraper system through a roller forming part of the scraper system, which engages the document storage roller, acting as an end stop. The scraper system thus experiences unwanted radial motion during storage and dispensing of documents. This radial motion can cause the scraper to lift off the band, and the leading edge of documents may then not be engaged by the scraper, if the scraper does not reestablish contact with the band quickly enough.

In one aspect of the invention, there is provided a document storage device for storing sheet documents, the device comprising a band, which can be wound onto a document storage roller such that sheet documents can be stored between adjacent windings of the band on the document storage roller and which can be unwound from the document storage roller thereby dispensing the stored documents, and a scraper assembly rotatable about a pivot and comprising a scraper and an end stop, each for contacting the band on the document storage roller, the scraper assembly being urged by a first biassing element such that the end stop maintains contact with the band on the document storage roller at a point distal from the pivot relative to the point of contact of the scraper with the band on the document storage roller.

By repositioning the end stop relative to the prior art, and thereby ensuring that the point of contact between the end stop and the document storage roller is further from the pivot than the point of contact between the scraper and the document storage roller, the amount of motion suffered by the scraper as a result of the radial motion picked up by the end stop is very much reduced. This is because the amount of rotation around the pivot caused by the radial motion is reduced as the end stop has been moved further away from the pivot than the scraper. Thus, the abovementioned problem has been overcome.

The biassing element is normally a helical spring. By reducing the amount of rotation around the pivot, the force exerted by this spring is more or less constant and is more predictable and controllable. This helps reduce damage caused by continuous bouncing of the end stop against the document storage roller as high peak forces caused by large radial motion of the end stop are less likely to be encountered. In the past, it has been found that the band can become damaged or even suffer movement along the axis of the document storage roller as a result of these peak forces.

Furthermore, by placing the end stop as described, the scraper assembly can approach the document storage roller more closely. This allows the first pinch roller of a transport system to be disposed more closely to the document storage roller for more reliable transportation of documents.

The documents are typically dispensed from the document storage roller at a point between the points of contact of the scraper and the end stop with the band on the document storage roller. The band is also withdrawn from the document storage roller at the document dispensing point, and of course, lies adjacent the document between the document and the end stop.

In a preferred embodiment, the end stop is a roller. For example, it may be a bearing roller, a ball race or a needle roller, and it may be made from a suitable metal, such as steel, or from a suitable plastic material, such as nylon. Alternatively, the end stop may simply be a non-rotating follower.

The document storage device normally further comprises a band roller upon which the band may be wound.

The band can be selectively wound between the band roller and the document storage roller so as to store and dispense documents from the document storage roller.

In a preferred embodiment, the band is entrained around one or more rollers mounted on the scraper assembly.

The documents are typically conveyed to the document storage roller via a document transport system. The document transport system may comprises a belt drive for delivering the documents to and from the band. The document transport system preferably comprises a diverter for diverting documents either into the document transport system or into an alternative document path.

The scraper assembly normally comprises a support to which the scraper is pivotally mounted. The scraper is preferably urged by a second biassing element towards the document storage roller. The scraper may be formed from a resilient material.

In a preferred embodiment, the document storage roller and the band roller are driven by independent motors.

An embodiment of the invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 shows the document storage device when the document storage roller is empty; and

FIG. 2 shows the document storage device when the document storage roller is full.

FIGS. 1 and 2 show a document storage device, typically for banknotes. In FIG. 1, the device is shown in a state where no documents have been stored, and in FIG. 2, the device is shown full to capacity.

As can be seen from FIGS. 1 and 2, the device, often known as a roll storage module, comprises a band roller 1 and a document storage roller 2, with a band 3 extending between them. The band 3 is entrained about rubber roller 4, roller 5 and drive roller 6 on its path between band roller 1 and document storage roller 2.

The band roller 1 and the document storage roller 2 are each driven by respective independently controlled motors, only one of which is shown at 7. By driving the two motors 7 in a storage direction, the band 3 is transferred from the band roller 1 to the document storage roller 2, as shown in FIG. 2. By reversing the direction (i.e. driving in a dispensing direction), the band 3 is transferred from the document storage roller 2 to the band roller 1, as shown in FIG. 1.

As the band 3 is transferred from the band roller 1 to the document storage roller 2 or vice versa, the rubber roller 4, roller 5 and drive roller 6 are driven by the band 3. Rubber roller 4 is fitted with a sensor 11 which detects the length of band 3 that has been transferred (and, by derivation, the speed of transfer of band 3). This sensor 11 typically comprises a disc (not shown) with slots provided around its circumference. Light emitted by a light emitting diode (not shown) is interrupted and transmitted intermittently as the disc rotates with the rubber roller 4. The transmitted light is detected by a detector (not shown) and this produces a pulsed output from sensor 11. By knowing the linear distance of travel of band 3 that corresponds to each pulse, it is possible to monitor the distance travelled by the band by counting the pulses. The speed of travel of the band 3 can be determined by measuring the time between pulses.

Drive roller 6 is connected to a gear (not shown) that meshes with gear 8. In turn, this meshes with a gear (not shown) connected to transport roller 9. Thus, as band 3 drives the drive roller 6, the transport roller 9 is caused to rotate. This drives the transport belt 10, which is entrained about transport roller 9 and another roller (not shown) at its upper end. The transport belt 10 forms a pinch at its upper and lower ends with rollers 12 a and 12 b respectively.

Rollers 13, diverter roller 14 and rollers 16 form part of an external transport system. They cooperate with corresponding rollers or belts that are not shown to convey documents along a transport path defined between the rollers 13, diverter roller 14 and rollers 16 and the corresponding rollers or belts. A diverter 17 is provided which can be moved into a diverting position to cause a document to be diverted from this transport path. If the diverter 17 is in the diverting position then a document, after being conveyed past rollers 13, is forced by the diverter 17 into the pinch between diverter roller 14 (which is driven by the external transport system) and pinch roller 15. Otherwise, the document is conveyed onwards to rollers 16. Diverted documents are picked up by the pinch between transport belt 10 and roller 12 a.

A document sensor system 18 is provided adjacent the transport belt 10. This can detect the passage of a document. Hence, it can be used to confirm that a diverted document has been safely conveyed to the document storage roller 2, or to detect a jam, for example, if diverted document is not detected within a predetermined period of time after it has been diverted from the external transport system. The sensor system 18 works by detection of reflected or transmitted light.

The roller 5, drive roller 6, transport roller 9, transport belt 10 and rollers 12 a and 12 b are all mounted on a rotatable scraper assembly. Also mounted on this scraper assembly are a scraper 19 (made from a suitable plastic such as polyamide-66, which may be reinforced with glass fibres) and a bearing roller 20. The entire assembly is free to rotate around a pivot 21. It is biassed to rotate towards the document storage roller 2 by way of a helical spring 22. This causes the assembly to be pulled towards the document storage roller 2 such that the bearing roller 20 makes contact with it. In effect, bearing roller 20 is acting as an end stop to the rotation of the scraper assembly around pivot 21.

The scraper 19 is pivotally mounted on the scraper assembly at pivot 23. It is independently biassed towards the document storage roller 2 by way of a second helical spring 24, extending between pivot 21 and a hook 25 on the scraper 19.

The operation of the device will now be described. When a document being conveyed along the external transport is to be stored, the diverter 17 is moved to the diverting position to cause the document to be diverted into the pinch between diverter roller 14 and pinch roller 15.

As the document is driven through diverter roller 14 and pinch roller 15, the motors 7 driving the band roller 1 and document storage roller 2 are driven in the storage direction so that the band 3 is transferred from the band roller 1 via the rubber roller 4, roller 5 and drive roller 6 to the document storage roller 2.

This causes the transport belt 10 to be driven from drive roller 6 via gear 8 and transport roller 9. The document to be stored is thus picked up in the pinch between the transport belt 10 and the pinch roller 12 a. It is conveyed to the pinch between transport belt 10 and the pinch roller 12 b. The document to be stored is then entrapped between the band 3 as it passes from drive roller 6 to the document storage roller 2 and the band 3 already wound onto document storage roller 2. Thus, the document is stored between adjacent windings of the band 3 on the document storage roller 2. Further documents may be stored in this way until the entire band 3 has been transferred from band roller 1 to the document storage roller 2. This can be detected by sensor 11 if the length of band 3 is known.

As more documents are stored, and thus more of band 3 is transferred to the document storage roller 2, the diameter of document storage roller 2 effectively increases. This can be seen clearly in FIG. 2, in which the diameter of the document storage roller 2 is approximately 125 mm compared to approximately 60 mm in FIG. 1 when no documents are stored, and the diameter of the band roller 1 has correspondingly reduced from approximately 74 mm to approximately 29 mm.

Due to the increase in diameter of the document storage roller 2, it is necessary for the scraper assembly to rotate around pivot 21 to accommodate the increase in diameter and to ensure that documents are delivered correctly. Bearing roller 20 forces the scraper assembly to rotate around pivot 21 as the diameter of the document storage roller 2 increases because it bears on the outermost revolution of band 3 on the document storage roller 2.

As the diameter of the document storage roller 2 increases, the optimum angle for scraper 19 to make contact with the band changes. By allowing scraper 19 to pivot around pivot 23 (under the spring tension of helical spring 24), the optimum angle can be maintained. As can be seen from the detailed sections “A” shown in FIGS. 1 and 2, when the diameter of document storage roller 2 is at a minimum the angle subtended between the scraper 19 and the band 3 is 57.5°, and when the diameter is at a maximum the angle is 72.2°. Thus, the optimum angle is maintained at all times.

When it is desired to dispense a document, the motors 7 are driven in the dispensing direction, opposite to the storage direction. Thus, the band 3 is transferred back from the document-storage roller 2 to the band roller 1. This has the effect of releasing notes from between the adjacent windings of the band 3 on document storage roller 2 as the outermost winding is removed from the document storage roller 2 and withdrawn towards the band roller 1. The leading edge of each document is engaged by the scraper 19 as it is released from the band 3. Effectively, the scraper 19 prevents the document from adhering to the band 3 and ensures that it is picked up by the pinch between transport belt 10 and roller 12 b. The document can then be driven back out of the device onto the external transport system for subsequent handling.

As more and more documents are dispensed, the diameter of document storage roller 2 diminishes again, whilst that of band roller 1 is augmented as it withdraws the band 3. The helical spring 22 acts to rotate the scraper assembly towards the document storage roller 2 as its diameter diminishes, limited by the bearing roller 20. Since the bearing roller 20 is relatively far away from the pivot 21 compared with the scraper 19, the movement of the scraper 19 caused by angular rotation around pivot 21 as a result of radial motion imparted to bearing roller 20 as the document storage roller 2 dispenses documents is minimised. This helps scraper 19 to maintain contact with the band so that it can reliably engage the leading edge of documents being dispensed. 

1. A document storage device for storing sheet documents, the device comprising a band, which can be wound onto a document storage roller such that sheet documents can be stored between adjacent windings of the band on the document storage roller and which can be unwound from the document storage roller thereby dispensing the stored documents, and a scraper assembly rotatable about a pivot and comprising a scraper and an end stop, each for contacting the band on the document storage roller, the scraper assembly being urged by a first biassing element such that the end stop maintains contact with the band on the document storage roller at a point distal from the pivot relative to the point of contact of the scraper with the band on the document storage roller.
 2. A document storage device according to claim 1, wherein the documents are dispensed from the document storage roller at a point between the points of contact of the scraper and the end stop with the band on the document storage roller.
 3. A document storage device according to claim 1, wherein the end stop is a roller.
 4. A document storage device according to claim 1, further comprising a band roller upon which the band may be wound.
 5. A document storage device according to claim 4, wherein the band can be selectively wound between the band roller and the document storage roller so as to store and dispense documents from the document storage roller.
 6. A document storage device according to claim 1, wherein the band is entrained around one or more rollers mounted on the scraper assembly.
 7. A document storage device according to claim 1, wherein the documents are conveyed to the document storage roller via a document transport system.
 8. A document storage device according to claim 7, wherein the document transport system comprises a belt drive for delivering the documents to and from the band.
 9. A document storage device according to claim 7, wherein the document transport system comprises a diverter for diverting documents either into the document transport system or into an alternative document path.
 10. A document storage device according to claim 1, wherein the scraper assembly comprises a support to which the scraper is pivotally mounted.
 11. A document storage device according to claim 10, wherein the scraper is urged by a second biassing element towards the document storage roller.
 12. A document storage device according to claim 1, wherein the scraper is formed from a resilient material.
 13. A document storage device according to claim 4, wherein the document storage roller and the band roller are driven by independent motors.
 14. (canceled) 